Microsoft is two days away from launching its long-awaited Windows Vista operating system. Windows Vista introduces a plethora of new features and enhancements that allows for greater security, a sleek new user interface and ease of use.

As with all new operating systems, however, new hardware may be required to take advantage of all the new features. Microsoft has devised a new rating system that will hopefully simplify future hardware and software purchases as well as give users a basic idea of the capabilities of a PC – say hello to the Windows Experience Index.

The new Windows Experience Index evaluates a systems performance right before the user sees the Windows desktop after a clean installation. It evaluates five subsystems and rates the system on a higher-is-better scale starting with 1.0. Processor, memory, graphics, gaming graphics and hard disk performance are the subsystems rated by the Windows Experience Index.

After evaluating the different subsystems, the system determines a base score of the system that is simply the score of the lowest performance subsystem and not an averaged overall score. The base score of the system determines the computing capabilities of a system. Microsoft offers a general description of system capabilities according to the base score in the Windows Vista What is the Windows Experience Index help file.

According to the Microsoft help file, a system with a base score of 1.0-2.0 is sufficient for basic productivity such as browsing the web and running office applications but lacks the horsepower to run Windows Aero or advanced multimedia functionalities such as Windows Media Center. Moving up to a score of 3.0 is a system that has enough power to run Windows Aero at a resolution of 1280x1024 and a few multimedia features such as standard definition video playback.

A score of 4.0-5.0 has the power necessary to take advantage of all Windows Vista functionality including Windows Media Center and audio/video streaming capabilities. The 4.0-5.0 rated system should also be capable of high definition video recording and playback, though recording will need a TV tuner. This also means the system will be able to play games sufficiently too. The help file also claims 5.0 is the highest base score of “the highest performing computers available when Windows Vista was released.” DailyTech's test system was able to produce subscores of 5.9 with relatively modest enthusiast hardware.

In addition to the base scores, Microsoft allows users to view the individual subsystem scores too. Microsoft claims “If your base score is not sufficient for a program or Windows Vista experience, you can use the subscores to help you figure out which components you need to upgrade.” This should theoretically help end users decide which component to upgrade when their system lacks the power to run new applications.

Microsoft’s Windows Experience Index help file also outlines the recommended subsystem scores for office productivity, gaming and graphic-intensive applications and the Media Center experience. For office productivity tasks, Microsoft recommends higher-the-better scores in CPU and memory categories while scores of at least 2.0 in the other categories should be sufficient.

Gamers will want to pay closer attention to scores in the memory, desktop graphics and 3D-gaming graphics categories while subsystem scores of at least 3.0 in the other categories will offer a decent gaming experience.

Multi-media buffs that want to take advantage of Windows Media Center integrated in Windows Vista Ultimate and Home Premium editions will want high subsystem scores in CPU, hard disk and desktop graphics categories. Subsystem scores in the memory and 3D graphics categories are not too important, though Microsoft recommends a score of 3.0 or higher in those categories.

Software companies should easily be able to specify recommended base or subsystem scores for optimal performance in addition to the typical recommended system requirements. This should allow the general consumer to purchase software that fits the potential of their PC instead of having to spend countless hours with tech support questioning why the software does not work.

The Windows Experience Index will be particularly helpful with Microsoft’s Game for Windows initiative, though DailyTech’sGame for Windows branded copy of Lego Star Wars II: The Original Trilogy makes no mention of the Windows Experience Index.

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